I don't often attempt to fly when walking across campus, but yesterday I gave it a try. I was going to the science library to retrieve some books on dreaming. About halfway there, in the wide-open mostly-empty quad, I spread my arms, looked at the sky, and added a leap to one of my steps.
My thinking was this: I was almost certainly awake -- but only almost certainly! As I've argued, I think it's hard to justify much more than 99.9% confidence that one is awake, once one considers the dubitability of all the empirical theories and philosophical arguments against dream doubt. And when one's confidence is imperfect, it will sometimes be reasonable to act on the off-chance that one is mistaken -- whenever the benefits of acting on that off-chance are sufficiently high and the costs sufficiently low.
I imagined that if I was dreaming, it would be totally awesome to fly around, instead of trudging along. On the other hand, if I was not dreaming, it seemed no big deal to leap, and in fact kind of fun -- maybe not entirely in keeping with the sober persona I (feebly) attempt to maintain as a professor, but heck, it's winter break and no one's around. So I figured, why not give it a whirl?
I'll model this thinking with a decision matrix, since we all love decision matrices, don't we? Call dream-flying a gain of 100, waking leap-and-fail a loss of 0.1, dreaming leap-and-fail a loss of only 0.01 (since no one will really see me), and continuing to walk in the dream a loss of 1 (since why bother with the trip if it's just a dream?). All this is relative to a default of zero for walking, awake, to the library. (For simplicity, I assume that if I'm dreaming things are overall not much better or worse than if I'm awake, e.g., that I can get the books and work on my research tomorrow.) I'd been reading about false awakenings, and at that moment 99.7% confidence in my wakefulness seemed about right to me. The odds of flying conditional upon dreaming I held to be about 50/50, since I don't always succeed when I try to fly in my dreams.
So here's the payoff matrix:
Leap = (.003)(.5)(100) + (.003)(.5)(-0.01) + (.997)(-0.1) = approx. +.05.
Not Leap = (.003)(-1) + (.997)(0) = -.003.
Of course, this decision outcome is highly dependent on one's degree of confidence that one is awake, on the downsides of leaping if it's not a dream, on the pleasure one takes in dream-flying, and on the probability of success if one is in fact dreaming. I wouldn't recommend attempting to fly if, say, you're driving your son to school or if you're standing in front of a class of 400, lecturing on evil.
But in those quiet moments, as you're walking along doing nothing else, with no one nearby to judge you -- well maybe in such moments spreading your wings can be the most reasonable thing to do.